


Oh Brother!

by Sinsational_Sinnabon



Category: Undertale (Video Game)
Genre: Fontcest, M/M, Sans is a very fucked up skeleton, Starring the thirsty skelefuckers of the internet, Unhealthy Relationships, implied fontcest
Language: English
Status: Completed
Published: 2016-10-13
Updated: 2016-10-13
Packaged: 2018-08-22 05:17:02
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,721
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/8274254
Author URL: https://archiveofourown.org/users/Sinsational_Sinnabon/pseuds/Sinsational_Sinnabon
Summary: The surface world was nothing like they'd imagined. It was harsh, and cruel, and unfair to all who dared to be different from what the humans had accepted as "normal". They were taken advantage of and fetishized in the same stroke of the brush. Sans would do anything to give Papyrus the life he'd always dreamed of, even if that meant taking the sort of jobs reserved for dark nights and locked doors.Because to Sans, his brother was everything.





	

**Author's Note:**

> To celebrate my Undertale blog getting 150 followers, I said I would write a few submitted prompts from the people who continue to support me! 
> 
> This is the first of 3 writing prompts I got, which sent me into the realm of Fontcest. In retrospect, this turned out kind of dark, but while I don't make a habit of writing fontcest, I promise that my view of the ship isn't entirely reflected in this work. I love me some brotherly fluff - I just like to make my characters hurt. 
> 
> This is dedicated to the tumblr user Ultrascarlet! Thanks for the submission and I hope you enjoy this! I had a lot of fun writing it!

It was a little over a year since the barrier had fallen, and monsters had left the underground for the surface world. Describing the first few weeks of their freedom as “chaotic” was a large understatement; the humans put up an absolute hissy fit when they learned of the existence of an entirely new race of sentient beings. Monsters went from being the villains in movies and the focus of horror stories to a political pain in the humans metaphorical ass.  If they weren’t complaining about how the Monsters would strain their resources and take their jobs, then they were bitching about  _ differences _ and  _ segregation _ and how these “demons” would steal their women. It was honestly idiotic.

 

Sans wasn’t a baby bones. He knew that it was all just a front to disguise their nasty stereotyping and fear. His opinion of humans wasn’t all that great to begin with, and his experiences trying to assimilate into the human community did nothing to wash the dirty taste from his mouth. His physical make up was apparently synonymous with “death” in their culture, and not a day went by where he wasn’t either screamed at, cursed out, or spit on. Didn’t exactly match his vision of what life above ground would be like. It was the same for most of the others.  Laws in their favor developed slowly, and the accommodations they were allowed came at a high price. But they were on the surface, so everyone was expected to play happy. 

 

So they did.

 

They spread out, tried to garner as little attention as possible. They were just too weak, and with intent meaning so much to the physicality of monsters, the humans and their hate were just too strong. Many were “homeless” for a good while, but this was nothing new after scrounging underground for centuries. Their king and queen tried their best, but eventually even the royal mandate was to “keep your head down, keep hope, and wait.” It was all they ever did. It was their past, their present, and would probably be their future for as long as they lived.

 

The months wore on, and eventually something else caught the human’s attention. He couldn’t remember exactly what. With all the shootings and movie actor drama and political scandals it was honestly a blur to him. God they were so fickle. The media lost interest and their race was left alone to live their mediocre day to day lives in dingy apartments with exorbitant rent, working jobs that no one else dared to take. The above accurately described the life of Sans the Skeleton. It took months of grueling work at a number of suspicious jobs, but the older of the brothers had finally saved up enough money to move out of Toriel’s place and into a shitty apartment on the outskirts of town. It was in a crime ridden neighborhood, and was infested with cockroaches that could be mistaken for small dogs, but it had windows. More importantly, it provided them with a sense of privacy that they hadn’t indulged in in months. Toriel was… nice, but almost too motherly. Especially since living with the goat monster meant also living with  _ Frisk _ . That kid gave him the fuckin creeps! They acted pleasant enough around him, but every time he met the kid’s eye, a searing ghostly pain dragged over his ribcage like a hot iron. Freaky was what it was. But Toriel was fond of the brat, and was nice enough to give him and Papyrus the spare room, so he tried to play nice. But the house was cramped, and Sans felt that he had to tiptoe from place to place in an effort to keep the home “child friendly”. No cursing, no dirty jokes, and bringing in his clients in secret was an endeavor that James Bond would appreciate.

 

That was one of his “jobs”. As much as humans pretended to hate monsters, he had discovered more than a handful found them… exotic. Too different to give basic rights, he supposed, but apparently not different enough to keep them out of their perverted sexual fantasies. He was barely two months on the surface when he found the first posting on craigslist, offering a shit load of human money to… well, summon his dick, lay back, and do nothing. That pretty much matched his “ideal job requirements”, even if it meant getting touched and groped by sticky fleshy fingers and covered with all sorts of human fluids. 

 

What? It’s a living. And his brother would be so happy when he was able to surprise him with that shiny red convertible on his birthday next month.

 

Needless to say it didn’t take him long to become well known around that particular dark section of the internet. Entire forums dedicated to posting pictures they had unknowingly snuck during sessions. Threads discussing the feel of magical flesh in comparison to human genitalia.  He was the talk of the town. Fetishists and the curious filled his inbox with pictures, questions, offers; it was mostly the latter he took seriously. It was a good thing he slept so much growing up underground, the time he spent shut in his bedroom translated well to his new life. He didn’t sleep much anymore. 

 

He made sure his apartment had a separate bedroom so that Papyrus would never have to know what he did to support them. He would dust himself before he would subject his brother to any of the jobs that were willing to hire their kind: Drug trafficking, hitmen, test subjects, prostitution, and numerous other distasteful tasks for monsters that managed to operate under the notice of the law. Papyrus was all he had, and he would do absolutely anything to protect him. The happy go lucky, energetic adult was under the impression that the surface was perfectly fine. Sans made sure to emphasize the slivers of good he was able to find in the outside world, and brought his brother all sorts of toys and treats and curios. Papyrus wasn’t allowed outside without Sans by his side, not that he would’ve gone anywhere without his stout brother anyway. Looking on their relationship from the outside, it was extremely unhealthy. Sans alienated himself from everyone, and his obsession with protecting his younger sibling drove him to practically cut the tall, energetic skeleton off as well. It was dangerous outside. They were family, and all they needed was each other. 

 

Which is why the picture’s that began to pop up around his online forums were especially jarring. He was used to fan art. Once the internet got enough photos to get a vague idea of what he looked like (and even before then), people had rushed to capture his likeness in all sorts of ways. A lot of it was harmless, people who just found talking, grinning skeletons that often wore jackets and athletic wear fun to draw. He even had a couple of his favorites saved to his laptop. But if there was one thing he learned quickly about the human internet through his line of work, it was that everything,  _ everything _ , was about sex. More and more of the drawings started to feature him in less clothing, revealing bones that should never see the public light of day. The positions started to get raunchier and the expressions more seductive, his sacrum and coccyx usually thrust in the air for a tantalizing view. The humans loved his magical flesh and how he could use it to create certain parts out of nothing. Sometimes, just to keep things interesting, he would change up the shape, the size; it certainly seemed to please his artistically inclined and thirsty fans. He got a laugh over the fact that his dick seemed to look slightly different in every image. They even spent hours depicting his sexual endeavors with humans real and not, caught in pen and digital color. 

 

But this. This is where he drew the line. He just wasn’t enough for them; he’d introduced them to sweet monster skeleton sex and in his growing fame, he had almost forgotten that he wasn’t the only skeleton in town. The flash of red is what caught his eye, lights freezing in place and stuttering slightly when he got a better look at what was on his screen. 

 

Pa-Papyrus?! 

 

The skeleton in the drawing was missing his battle body, as well as… most of the rest of his clothes, but there was no mistaking it as the lanky form of his brother, wrapped in nothing but his trademark scarf. Hard fingers rattling against the desk, he speedily minimized the window and reeled back in his chair. He took in deep breaths that he didn’t actually need and stared blankly at his desktop photo - the two of them in Snowdin. 

 

Sans snapped the laptop closed with a click and rushed out of his room without a look back. This absolutely wouldn’t do. He wondered if Papyrus had seen these… these… pictures. He had fixed up their computer to automatically block anything related to his name, but he hadn’t even thought to do the same for his brother. Papyrus was too young. Too innocent. Too… His mind unwillingly recalled the image of his sibling in a compromising position brightly behind his eye sockets. 

 

He shook his head as if the motion would help drive away the mental picture. Papyrus may be inexperienced, and a bit naive, but had a sneaking suspicion that the other skeleton was less “innocent” than he appeared. No thanks to that fucking calculator Mettaton of course. After a few minutes Sans had managed to drag his mind away and distract it with other subjects - like what was for dinner tonight.

 

That was a trick question. It was pasta. It was always pasta.

 

He followed his nasal cavity into the small dingy kitchen, where Papyrus had just finished plating his nightly spaghetti creation. By the way the noodles sparkled, he had a sneaking suspicion that his brother had mistaken glitter for parmesan again. Plastering on a smile that hid the fact that he was dead tired and still a little shaken up, he thanked the lanky monster and took his plate to the couch. They didn’t have room for a table, so this is where they ate every night. He flipped on the TV and flopped down casually in his normal spot against the armrest. Papyrus settled himself much more gently right in the center of the couch, already invested in whatever drivelling human show was playing on the screen. 

 

It was a routine they repeated often, almost nightly, but Sans couldn’t help but notice that tonight felt… different. The air felt hot and stifling. Never before had he been so acutely aware of the small amount of cushion between him and his brother. His arms pressed harder into his side in an attempt to curl in on himself without drawing notice. Oblivious, as always, the towering figure beside him leaned over conspiratorially to whisper comments about the outcome of the show into the side of his skull. He was on his feet before he knew it, tailbone leaving the couch as if a spring was attached to the tip. 

 

“* uh- i just remembered i have work to do tonight!” He did, actually. There was an astronomy paper he was being paid to write lying on his desk, but it was the furthest thing from his mind. All he knew was that he had to get away - be alone for a little bit. Just long enough for him to shake whatever this weird feeling was around Papyrus. His heart plummeted when he turned to see his brothers face. He was smiling, but there was no mistaking a flicker of hurt beneath the toothy grin. With Sans so busy all the time, the time they spent together eating and watching television became somewhat sacred. But he just couldn’t. Not tonight.

 

“* i’m really sorry bro. I know i’ve been scarce, but the landlord raised rent on us again and i had to pick up a few extra jobs.” Again, not a complete lie. Papyrus sighed and hunched forward, resting his elbows on his bony knees. 

 

“Are you sure you’re alright brother? You are acting… strange. Normally you at least pretend to watch the show.” Another punch to the gut. It just served to prove how intuitive his younger brother was. Other people may say things behind his back, that he was simple and ignorant and childlike, but he knew better. His brother just had a soul of gold, and believed in the good in everybody. While it was a worldview he certainly couldn’t accept himself, it made Papyrus Papyrus, and Sans wouldn’t have it any other way.

 

“* i’m fine paps. Just… tired.” The tall skeleton drooped further at that. “* i’ll be along later to read you your bedtime story- how about that? i’ll even do the voices you like?” 

 

While sockets still searched his face curiously, it seemed to work. Papyrus set both of their empty plates aside and settled back into the couch to watch the show alone. Giving his brother one last apologetic look, he turned heel and shuffled back into his room. Shutting and locking the door behind him (a habit) he sat heavily at the desk, the weary office chair voicing a quiet complaint. He might as well  _ actually _ try and do work while he was holing himself up in here. The astronomy paper practically wrote itself. The pen made a satisfying scratch against the notepad as long words and terminology spun into educated sentences and convincing paragraphs. He poured himself into science, the notion that he was nothing more than a tiny speck in the scheme of the universe making his own problems seem tiny, insignificant. It was easy to lose himself in the inspiring but nihilistic thoughts. He didn’t matter. This didn’t matter. Nothing mattered. Any day now the kid would decide that they weren’t satisfied with this “happy ending” and send them all back underground. To anyone else the thought would be sobering, but in some fucked up way it was relieving to just give up control. His laptop sat closed on the edge of his bed and pulled at his vision with a hard-to-ignore presence. As hard as he tried, the temptation to open it up; to pull up the tab from before, was too great.

 

Fuck it. 

 

The wheels of the chair squeaked as a kick against the desk propelled him across the cramped room. It bumped against the bed and Sans plucked up the heavy metal rectangle from where it lay half buried in his sheets, holding it close as he rolled out of the chair and onto the mattress. The pinnacle of laziness indeed. Using his ball of musty covers as a pillow, he propped himself up and flipped up the top of the old PC. His soul thumped as the screen whirred to life, revealing his desktop and the minimized tab waiting at the bottom. His ceramic finger slid noisily against the touch pad. Nothing happened. A frustrated grumble snuck out under his breath. He fished around on the floor beside the bed until he found what he was looking for, prying the scrap of black fabric from a pile of dirty clothes. He pulled on the touchscreen glove hastily, fabric scratchy against his metacarpals. It turned out fleshless limbs were pretty useless on touch sensitive devices, which is why he usually used a mouse plugged into his computer. But when he wanted to use his laptop in bed… well, he was lucky humans had thought to invent this particular product. 

 

_ Swip, Swip~  _ The image from before filled the screen again, the flushed face and wide sockets of his younger brother staring at him seductively. While his face flushed, he forced himself to look, trying to decipher exactly what he was feeling. He had to go about this scientifically. He ticked off the reactions in his head as he went. Temperature, somewhat elevated causing flushing of the zygomatic arches. Soul seems to be beating at an irregular rate, and magic production is higher that usual. The majority of magic appears to be gathering at the junction of the pubis, as if responding to a state of aro u s  a  l .  .  .

 

Sans slammed his palms into his eyesockets. Oh sweet Asgore this was  _ not _ happening. Maybe it was just the position, or something else about the image. It didn’t mean that he was necessarily attracted to  _ Papyrus -  _ right? His arrow drifted up to the search bar in the upper corner of the screen. Perhaps he just needed to do a bit more research. That’s what a good scientist would do, obviously. Repeated testing of hypothesis and all that jazz. Gloved hand trembling in a mix of nervousness and anticipation, he clacked in his brother’s name and pressed “search”. 

 

The amount of orange and white that checkered his results page was horrifying. It seemed that the humans obsession with skeletons wasn’t personal to Sans in the least, and spilled right over onto anything they could latch onto. Slowly, the images began to stand out on their own instead of blurring together in a mishmash of color. His sibling in a variety of situations, poses; all sexual and seductive and enticingly erotic. Pupils small and bright, he took a certain detached pleasure in scanning over the array of brilliant white bones of the lanky skeletal figure. From the way his magic was reacting, it  _ definitely  _ wasn’t just that one image, but the monster depicted in them. The monster that he lived with and ate with and practically raised from a babybones. His  _ brother _ . 

 

A splash of blue caught in the edges of his vision, and he selected it automatically. Holy fucking shit. While he had just come to the realization that he liked his sibling in less than innocuous ways himself, the humans had been busy for quite a while. What did Alphys call this particular human custom? Oh yeah - “shipping”. They knew of his relations to Papyrus, yet here was an entire page of pictures of him pressed against the taller monster; bone against bone. He didn’t want to look, in fear that once the image was set into his mind that it would sit there like a piece of the Core, begging to be attended to and acted on. 

 

Curiosity killed the cat, and he’d already come this far. He shouldn’t  _ pussy _ out now. Laughing wryly at his tense attempt at humor, he brought up the image that had first caught his eye. They seemed to be on a bed, sheets bunched up around their feet. Papyrus was beneath him, shyly looking away from the camera as his older brother slid his thick fingers between the gaps of his delicate ribs. The lights in his own eyes were trained piercingly on the viewer, left lit up in a brilliant blue gaze. His smile was hungry. 

 

His shorts were uncomfortably now too tight, his summoned magic pressed against the warm metal of his laptop separated by the thin fabric. His breath came in short heated pants. He couldn’t tear away, and his free hand traveled down of it’s own accord to paw at the apparent bulge. Maybe… just once wouldn’t hurt. He wouldn’t finish. He wouldn’t!  But his cock was begging for  _ some _ sort of attention, and the desire for friction had his fingers toying with the waistband of his shorts in seconds, soft scrapes sounding from where he brushed against his pelvic arch. He was so close - the heat from his erection painting his hand when there was a loud knock on his bedroom door. 

 

“SANS! I’m heading to bed now! You promised to read to me!”

 

There was a loud thunk in return as his laptop was flung from his lap onto the floor, the short skeleton yanking his hand from inside of his pants like his dick was going to burn him. Throwing the sheets back, he made to stand. He was still rock hard, and the way the fabric of his shorts moved against the magical organ pulled a needy whimper from the back of his throat. Of all the inconvenient, horrible, bad times Papyrus could’ve picked to knock…

 

At the thought of his brother again, his cock gave an insistent twitch. His fingers mimicked the motion, but another glance toward the door told him that Papyrus wouldn’t wait. Instead he roughly shifted it so that it was a bit less visible and pulled his shirt down to cover as much as he could. He bent down to pick up the fallen computer, placing it back on the bed. He glanced at the image on the screen for one last, long moment before closing the tab. His own expression was burned into his mind, cocky smile and teasing eyes. “This could be you.” He seemed to say, his double running his fingers down the ribs of the tall skeleton pinned beneath him. The eyes that flicked at the closed door once more held an entirely different heat. 

 

Their life on the surface wasn’t great. They lived in a cramped apartment, in a bad part of town, in a world where everyone hated them. Any day, what little comfort they had could be ripped away from them by a child who treated their existence as a game to be played. There was blood on his hands, in this timeline and others. He’d done illegal things - immoral things. He whored himself out to give Papyrus the best life he possibly could. Papyrus. His reason for life. His everything.

 

He kept a lot of secrets from his brother.

 

A miniscule grin hiked at the corner of his mouth as he opened the door and joined his sibling in the hallway. His eyes roved across bone and magic, seeing everything in a different light. Tonight, he was going to read Papyrus a story. He would do the voices and tuck him into bed when he fell asleep before the end. Then, he was going to come back to the safety of his room and fuck himself to the thought of his brother writhing beneath him. Wanting him.  _ Needing  _ him.

 

Sans had so many secrets. What was one more?

  
  



End file.
